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17 The Healthy Person with an Abnormal Genetic Test Result: The Difference between a Presymptomatic or Asymptomatic Carrier and an Obligate Carrier
For example, women with a fragile X premutation have been traditionally thought of
as healthy obligate carriers, but it is now known that some of these women experience
premature ovarian insufﬁciency as an expression of the disease (McConkie-Rosell
et al., 2005).
Figure 3.9 demonstrates how to document genetic test results and asymptomatic
or presymptomatic and obligate carrier status. Individuals who are obligate carriers
are represented on the pedigree with a dot in the middle of the male (square) or
female (circle) symbol. Persons who are asymptomatic or presymptomatic carriers
are represented with a line down the middle of the pedigree symbol. If the person
later develops the disease, the symbol is shaded.
3.18 PEDIGREE ETIQUETTE
3.18.1 The Skeletons in the Closet
For many reasons, people tend to keep genetic information private. There is often a
sense of stigma, even embarrassment about “bad blood” or a “curse” in the family. As
Francis Galton observed, “Most men and women shrink from having their hereditary
worth recorded. There may be family diseases of which they hardly dare to speak,
and then in whispered hints or hushed phrases as if timidity of utterance could hush
thoughts. . .” (Resta, 1995). People may be reluctant to share medical and genetic
information because of fear they will be blamed for the family imperfections.
3.18.2 Choose Your Words Wisely
The difference between the right word and the almost right word is the difference
between lightening and the lightning bug.
When you take a medical-family history, you are inquiring about the very essence
of an individual. You are asking not only about the individual’s personal health but
also about intimate relationships and the health of family members (with whom he
or she may have little contact). Before you begin taking a genetic family history, it
is helpful to warn the client: “I need to ask you some personal questions about your
health and the health of people in your family. Your answers to these questions are
an important part of providing you with appropriate medical care.”
The clinician should be careful not to perpetuate feelings of guilt or fears of
stigmatization. Use words such as altered, changed, or not working properly to
describe genes, instead of mutation, bad, or faulty. Emphasize to the patient that
relatives have no choice in the genetic conditions that are passed in a family; the
diseases are nobody’s fault.
Be sensitive to terms like an uneventful pregnancy. Although a healthy pregnancy
may be uneventful to the clinician, it is very eventful to the proud parents! I often
GETTING TO THE ROOTS: RECORDING THE FAMILY TREE
hear clinicians refer to a family history without apparent genetic problems as a
“negative” family history, as compared to “positive.” A positive family history is
usually experienced as negative by the patient and family (Fisher, 1996). I usually
describe health problems in the family history as being contributory or remarkable as
compared to noncontributory or unremarkable in reference to the medical problems
Questioning should focus on “people-ﬁrst-language” (www.disabilityisnatural.
com), with inquires about the diagnosis not the label (e.g., a person with Down
syndrome not a Down’s person, or a person with autism not an autistic). It is a
challenge in taking a family history not to focus solely on health problems, but it is
important not to use words with negative connotations such as abnormal, crippled,
retarded (intellectual disability is appropriate), birth defect (congenital disability is
preferred), or wheelchair bound (as compared to saying the person uses a wheelchair
or mobility devise). Avoid phrases that ask if relatives “suffer” or “struggle” from a
Ask questions one at a time. Do not jump from one topic to another. Begin
with general questions, and then move to more speciﬁc questions that may be more
complex or threatening (McCarthy Veach et al., 2003). Do not interrogate.
The ultimate test of the appropriateness of a question is “Will this information
be helpful to my patient” (Hill and O’Brien, 1999). If the patient asked you, “Why
do you need to know this information?” what would be your reply (McCarthyVeach
et al., 2003)?
3.18.3 Use Common Language
You are more likely to be successful in obtaining an accurate family history if you use
terms that are familiar to people. For example, rather than asking about myopathies
in the family, inquire if individuals have muscle weakness or if anyone uses a cane
3.18.4 Beware the Leading Question
If you say, “So, your brothers and sisters are healthy, right? No health problems in
your parents?” you will most likely receive a reply of “Un-huh,” regardless of whether
this is a true statement. Instead, try to be speciﬁc with your questioning by asking
open-ended questions: “Do your brothers and sisters have any health problems?”
Let your client tell his or her story. If the client’s dialogue is heading down a path that
is not leading to information relevant for your evaluation, gently lead the questioning
back on task. For example interject with, “That is interesting information. Now let
me ask you more about . . .”
Respect a client’s belief system of causality of a problem. Be aware of the emotional and cognitive effect that your history gathering is having on your client, and
slow your pace of questioning or pause as needed (Stanion et al., 1997).
3.18.6 Acknowledge Signiﬁcant Life Events
Common courtesy should be the rule in taking a family history. If a woman tells you
that she recently miscarried or that her mother died of breast cancer a few months
ago, it is appropriate to acknowledge this with “I am sorry to hear of your loss,”
or “This must be a difﬁcult time for you.” Conversely, the news of a recent birth,
marriage, or desired pregnancy can be greeted with “Congratulations.”
Each family history tells a story. Sometimes that story leaps from the page and
must be acknowledged. A person may be the only survivor from a house ﬁre or a car
accident that took the lives of several relatives. A family may have perished in the
Holocaust or from a similar criminal act against humanity. Your comments such as
“That must have been hard for you,” or “I cannot imagine what that must have been
like for you,” in acknowledgment of such obviously life-changing events up-rooted
in the family tree, will be appreciated by your client and assist in cementing rapport,
respect and trust with your patient.
3.18.7 Be Sensitive to Cultural Issues and Differences
If your patient does not speak English, get an interpreter. Do not rely on a family
member to provide interpretation. The family member may be tempted to interject
his or her opinions, particularly about family matters, as part of the translation or
omit or censor information. Using an interpreter can be problematic if the interpreter
is from the same social community as the patient; in this circumstance the patient
may be reluctant to share conﬁdential information.
Culture consists of shared patterns, knowledge, meaning, and behaviors of a social
group (Fisher, 1996). Individuals have different customs and beliefs based on their
race, socioeconomic status, gender, religious beliefs, sexual orientation, education, or
health status. When taking a family history, it is important to acknowledge belief systems that are different from one’s own. For example, a traditional Latino woman may
believe that her child’s cleft lip and palate is the result of supernatural forces during
a lunar eclipse, “susto” (Cohen et al., 1998). Individuals from a traditional Southeast
Asian culture may have strong belief in karma and fate. Several cultures believe
in the evil eye as a cause of family illness and woes (Abboud, 1998; Kaloﬁssudis,
2003). Traditional Chinese views may relate genetics to Buddhist ideas of retribution
in this life for wrong-doings committed in a previous life. Accepted Chinese beliefs
are in patrilineal descent (through the male lines) and thus the male blood line is
genetically stronger and diseases can be passed through the male line more readily
than the female line (Barlow-Stewart et al., 2006). Persons from certain religious
and cultural groups may believe bad thoughts or sins cause a birth defect or genetic
disorder (Cohen et al., 1998). References to “bad illnesses” in the family may disturb
the “good aura” of the family or ancestors (Fisher and Lew, 1996).
GETTING TO THE ROOTS: RECORDING THE FAMILY TREE
An individual’s belief system is likely to inﬂuence the type of health information he
or she shares with the healthcare provider. A vivid example of this is the description of
a Hopi woman with severely disabling congenital kyphoscoliosis who was described
by her sister as being small and having pain in her legs and back that kept her from her
normal activities. The woman’s sister was not portrayed as disabled, because she had
high status in the community due to her ability to make piki, a thin wafer bread (Hauck
and Knoki-Wilson, 1996). While it is important to listen to and respect a person’s
cultural health beliefs, it is just as essential to avoid stereotypes by assuming that all
persons from that cultural share the same views of health and disease causation.
Exceptional references on providing healthcare for diverse populations are Cultural and Ethnic Diversity: A Guide for Genetics Professionals (Fisher, 1996), Developing Cross-Cultural Competence: A Guide for Working with Young Children and
Their Families, (Lynch and Hanson, 2004), Cultural Awareness in the Human Services: A Multi-Ethnic Approach (Green, 1999), and Counselling the Cultural Diverse:
Theory and Practice (Wing Sue and Sue, 2002).
3.19 RECORDING A BASIC PEDIGREE: THE QUESTIONS TO ASK
Obtaining an extended medical-family history is really no different from obtaining
a person’s medical history. I usually inform the consultand, “I will now ask you
questions about you and your relatives. I am interested in your family members who
are both living and dead.” Then I ask general questions, reviewing medical systems
from head to toe. If a positive history is found, I ask directed questions based on that
system, and the genetic diseases that are associated with it. For additional directed
family history questions focused on a positive family history for several common
medical conditions (e.g., heart disease, hearing loss), see Chapter 4.
3.19.1 Medical-Family History Queries by Systems Review
184.108.40.206 Head, Face, and Neck. Begin by asking, Does anyone have anything
unusual about the way he or she looks? If yes, have the historian describe the unusual
facial features. In particular inquire about unusual placement or shape of the eyes and
Anyone with an unusually large or small head?
Are there problems with vision, blindness, cataracts, or glaucoma? (If so, inquire
as to the age the problems began, the severity, and any treatment.)
Anyone with unusual eye coloring (e.g., eyes that are different colors, or whites
of the eyes that are blue)?
Do any family members have cleft lip or opening in the lip, with or without cleft
Anyone with unusual problems with his or her teeth (e.g., missing, extra, misshapen, fragile, early teeth loss)?
RECORDING A BASIC PEDIGREE: THE QUESTIONS TO ASK
Any problems with hearing or speech?
Anyone with a short or webbed neck?
Anything unusual about the hair (e.g., coarse, ﬁne, early balding, white patch)?
220.127.116.11 Skeletal System.
Is any family member unusually tall or short? (If so, record the heights of the
person, the parents, and siblings. If someone is short, is he or she in proportion?)
Anyone with curvature of the spine? (If so, did this require surgery or bracing?)
Anyone with multiple fractures? (If yes, inquire as to how many fractures, how
the breaks occurred, the bones that were broken, and the age the fractures
Anyone with an unusual shape to his or her chest?
Anyone with unusually formed bones?
Anyone with unusually shaped hands or feet, such as extremely long or short
ﬁngers or toes, missing ﬁngers or toes? Have the historian describe these
Anyone with joint problems, such that they are unusually stiff or ﬂexible, or
Anyone with unusual lumps, bumps, or birthmarks? (If so, have the patient describe
them, their location, their coloration, and number.) Were these skin changes
ever biopsied or treated?
Any problems with healing, scarring, or excessive bruising?
Anyone with unusual problems with their ﬁngernails, or toenails, such as absent
nails, or growths under the nails?
18.104.22.168 Respiratory System.
Any family members with any lung diseases? (If so, were they smokers? Were
they treated for the lung condition, and how?)
22.214.171.124 Cardiac System.
Anyone with heart disease? (If so, at what age, and how were they treated?)
Was anyone born with a heart defect? (If so, did they have birth anomalies or
Anyone with heart murmurs?
Anyone with high blood pressure?
Were there any heart surgeries? (If so, what was done, and at what age?)